Center Pivot Irrigation System Research Articles

Field Test of a Center Pivot Irrigation System

Field Test of a Center Pivot Irrigation System

Wheat Yield Response to Water Deficit under Central Pivot Irrigation System Using Remote Sensing Techniques

Scarcity of rainfall and limited irrigation water resources is the main challenge for agricultural expanding policies and strategies. At the same time, there is a high concern to increase the area of wheat cultivation in order to meet the increasing local consumption. The big challenge is to incerese wheat production using same or less amount of irrigation water. In this trend, the study was carried out to analyze the sensitivity of wheat yield to water deficit using remotely sensed data in El-Salhia agricultural project which located in the eastern part of Nile delta. Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) were extracted from Landsat 7. Water Deficit Index (WDI) used both LST minus air temperature (Tair) and vegetation index to estimate the relative water status. Yield response factor (ky) was derived from relationship between relative yield decrease and relative evapotranspiration deficit. The relative Evapotranspiration deficit was replaced by WDI. Linear regression was found between predicted wheat yield and actual wheat yield with 0.2?6, 0.025, 0.252 and 0.76 as correlation coefficient on 30th of Dec. 2012, 15th of Jan. 2013, 16th of Feb. 2013 and 20th of Mar. 2013 respectively. The main objective of this study is using a combination between FAO 33 paper approach and remote sensing techniques to estimate wheat yield response to water.

Effect of microalgae application on soil algal species diversity, cation exchange capacity and organic matter after herbicide treatments

Soil microalgae live on small communities that change structure depending on many factors. Some of these factors include soil pH, agricultural practices as well as pesticide and herbicide treatments. The size and activity of these soil microbial communities is an indicator of health, quality and fertility necessary for sustainable agriculture. Methods:A commercial proprietary suspension of microalgae GOgreen®was applied at different concentrations through a center pivot irrigation system to a crop of cultivated corn (Zea mays) during six months. Experimental plots of 0.5 acres each were planted in four rows. Corn (34,000 plants/acre) was planted in May and harvested in November allowing each plot to be studied for 6 months. In addition, one plot was planted for a second year to study the effects of consecutive planting and harvesting on algae populations in the soil. Soil samples were collected at a depth of 6 inches. Microalgae species identification was based on morphological criteria. Soil analysis included organic matter content (OM), pH and cation exchange capacity (CEC).Results:Treatment with GOgreen®has significant and measurable positive effects on soil OM content, CEC, pH and microalgae species diversity.Conclusions: It was demonstrated through this study that GOgreen®increased diatom numbers and microalgae species diversity showing a restorative effect on soil quality after herbicide treatment in heavily farmed soil. Additionally, GOgreen®lowers the pH in soils with a pH higher than 7.0 emerging as an economical alternative that is safe for humans and the environment.

DESIGN OF CENTER PIVOT IRRIGATION SYSTEM BASED ON SIMULATION MODEL TECHNIQUE

Centre pivot irrigation system is a promising and precise system, for increasing the utilization efficiency of unit water. Hence, A CPIM simulation model has been developed and validated, however, A CPIM model is based on crop type, weather data, and soil characteristics. The model comprises five sub-models for: (a) main sub-model; (b) data entry sub-model; (c) weather sub-model; (d) irrigation sub-model; and (e) results sub-model. The most important simulation outputs of the CPIM model include nozzle flow rate (m3/h), application rate (mm/h), and throw diameter (m). These outputs (outputs of 9 scenarios) were compared with observed/manufactured data for the calibration and validation of the model. Results of this comparison show that differences in model accuracy owing to different variables affecting the design and management of the center pivot were not significant. The relationships between the observed/manufactured and simulated results have a good correlation with high value of coefficient of determination and the best models are as follows: 1- Nozzle flow rate (m3/h) was in scenario 5 with R2 = 0.967 and explained by an exponential model: Q SIM = 0.1067e4.1131 (Q obs). 2- Application rate (mm/h) was in all scenarios with a very high R2 and explained by a linear model. 3- Throw diameter (m) was in scenario 1 with R2 = 0.942 and explained by a power model: Dw SIM = 3.9064 (Dw MFD)0.4361.

Spatial mapping of evapotranspiration over Devils Lake basin with SEBAL: application to flood mitigation via irrigation of agricultural crops

Excessive precipitation since 1993 has produced extensive flooding in the Devils Lake basin in northeastern North Dakota, USA. Irrigation of agricultural crops has been proposed as a flood mitigation tool. Ten test fields were equipped with center pivot irrigation systems to compare test field evapotranspiration (ET) with ET for crops in the predominantly nonirrigated basin. An irrigation scheduling analysis indicated 2006 was a favorable year to estimate the maximum ET gains achievable via irrigation. An ET map for 2006 using the Surface Energy Balance Algorithm for Land (SEBAL) for 54 % of the basin, and land use and soil survey data, was used to compare ET estimates at the test fields with ET estimates across the study area. May–September ET was estimated by SEBAL as 394 mm for wheat and 435 mm for corn across the study area, while corn ET at irrigated test sites was 452 mm. Because the 17-mm ET advantage by irrigating corn was substantially smaller than the 41-mm ET advantage for corn versus wheat, we conclude widespread irrigation development to mitigate flooding is not justified. Coarse-textured soils exhibited some seasonal ET deficits, but their small areal extents and parcel sizes offer virtually no opportunity for flood mitigation.

Movable Surface Irrigation System (MSIS) Impact on Spatial and Temporal Distribution of Soil Moisture and salinity

Movable surface irrigation system (MSIS), was carried out by modification of center pivot irrigation system and depends on replacing the sprayers by polyethylene hoses ending by nozzles. Field experiments were conducted at farm on Alex-Cairo desert road, to assess moving surface irrigation system at 2012 year. The main aims of this research are to study spatial and temporal moisture and salinity distribution patterns under (MSIS), the modification of pivot irrigation system to be more suitable to irrigate some trees, and other high crops under special conditions, to evaluate the modification system and to reduce the investment costs of the modified system. Results show that, operating the (MSIS)at low pressure head (1.5 bar), water amount was saved by (16.8%)(Abdel-Rahman, 2005), the uniformity coefficient was 90.75%, beside, the movable surface system reduced the hazard of chemigation. Finally, High efficiency of applied water distribution, reduce deep- percolation, reducing runoff and having good management without exceed water irrigation by using (MSIS).

Does efficient irrigation technology lead to reduced groundwater extraction? Empirical evidence

Encouraging the use of more efficient irrigation technology is often viewed as an effective, politically feasible method to reduce the consumptive use of water for agricultural production. Despite its pervasive recommendation, it is not clear that increasing irrigation efficiency will lead to water conservation in practice. In this paper, we evaluate the effect of a widespread conversion from traditional center pivot irrigation systems to higher efficiency dropped-nozzle center pivot systems that has occurred in western Kansas. State and national cost-share programs subsidized the conversion. On an average, the intended reduction in groundwater use did not occur; the shift to more efficient irrigation technology has increased groundwater extraction, in part due to shifting crop patterns.

Investment recovery period in electric motor of higher efficiency in pumping for irrigation

In this study, it was adjusted a mathematical model to measure the effect of electric motor efficiency on pumping system costs for irrigation on the tariff structure of conventional electricity and green horo-seasonal , and also to calculate the recovery period of the invested capital in higher efficiency equipment. Then, it was applied to a center pivot irrigation system in two options of electric motor efficiency, 92,6% (standard line) and 94,3% (high efficiency line), and the acquisition cost of the first corresponded to 70% the of the second. The power of the electric motor was 100hp. The results showed that the model allowed us to evaluate if a high efficiency motor was economically viable compared to the standard motor in each tariff structure. The high efficiency motor was not viable in the two tariff structures. In the green horo-seasonal tariff, would only be viable if its efficiency was 4.46% higher than the standard motor. In the conventional tariff, it would only be viable if the efficiency overcame 2.71%.

Assessment of Soil Compaction under Center Pivot Irrigation Systems and its Effect on Crop Performance

A field study on two 12.5 ha plots cultivated with wheat and alfalfa was conducted to determine Soil Compaction (SC), its spatial variability and its effect on crop performance under center pivot irrigation systems. Considering compaction at two tested soil depths, results revealed that the soil of the alfalfa plot exhibited significantly (p

Rice Production with Center Pivot Irrigation

While continuous-flood irrigation, the most common method for U.S. rice production, can have a fairly high irrigation application efficiency, factors such as soil variability and the size of most Mid-South farming operations often combine to reduce the efficiency. Center pivot irrigation is a way to reduce irrigation water use in some cases and allow rice in the crop rotation in other situations when flooding is not practical. Rice was produced at the University of Missouri Fisher Delta Research Center Marsh Farm at Portageville in 2009 and 2010 and irrigated every other day with a 150-m-long center pivot irrigation system. An experimental crop coefficient function was developed and included in a beta version of the Arkansas Irrigation Scheduler (AIS). It was used with daily short grass reference evapotranspiration (ETo) calculated from weather data collected on site to estimate the daily soil water deficit (SWD). Weather conditions were warmer and much drier in 2010 and ETo was higher each month. In 2009, there were totals of 34 days with irrigation and 414 mm of water applied. In 2010, there were totals of 45 days with irrigation and 503 mm of irrigation water applied. In 2009, the cultivar Templeton had the highest observed grain yield (8.31 Mg ha-1) and irrigation water use efficiency (IWUE; 2.0 kg m-3). In 2010, the cultivar Francis had the highest observed grain yield (8.2 Mg ha-1) and IWUE (1.6 kg m-3). In addition to the higher temperatures in 2010, yields were probably impacted by the fact that rice was produced in the field the two previous years. Future research will use the beta version of the AIS to schedule irrigations, which should indicate whether the crop coefficient is adequate and allow producers a system for scheduling center pivot irrigation on rice.

A COMPUTER PROGRAM FOR MONITORING CENTRE-PIVOT IRRIGATION SYSTEMS

A computer programme was developed for the purpose of monitoring performance of centre pivot irrigation system. The program was written in “Visual Basic 6.0 Programming Language”. It was intended to calculate the main performance parameters of coefficient of uniformity (Cu), distribution coefficient (Du), and Scheduling coefficient (Sc). For verification of the model, four field trials were carried out during the period December 2007 - July 2008 at four schemes using centre pivot irrigation systems. The schemes were Ras Al Wadi Al Akhdar Project (رأس الوادى الأخضر مشروع ), El Bashir Company (البشاير شرکة), Tala Company (تالا شرکة), and the Arab Company for Agricultural Production and Processing (الشرکة العربية للانتاج والتصنيع الزراعى). The schemes were growing alfalfa, except El Bashir Company (شرکة البشاير) which was growing onion. Collected data were fed to the program. The program output was typical to that obtainable through manual calculation and could therefore relief operators from that burden. The program could offer a simple tool for calculating efficiencies for

Artificial neural networks for simulating wind effects on sprinkler distribution patterns

A new approach based on Artificial Neural Networks (ANNs) is presented to simulate the effects of wind on the distribution pattern of a single sprinkler under a center pivot or block irrigation system. Field experiments were performed under various wind conditions (speed and direction). An experimental data from different distribution patterns using a Nelson R3000 Rotator® sprinkler have been split into three and used for model training, validation and testing. Parameters affecting the distribution pattern were defined. To find an optimal structure, various networks with different architectures have been trained using an Early Stopping method. The selected structure produced R2= 0.929 and RMSE = 6.69 mL for the test subset, consisting of a Multi-Layer Perceptron (MLP) neural network with a backpropagation training algorithm; two hidden layers (twenty neurons in the first hidden layer and six neurons in the second hidden layer) and a tangent-sigmoid transfer function. This optimal network was implemented in MATLAB® to develop a model termed ISSP (Intelligent Simulator of Sprinkler Pattern). ISSP uses wind speed and direction as input variables and is able to simulate the distorted distribution pattern from a R3000 Rotator® sprinkler with reasonable accuracy (R2> 0.935). Results of model evaluation confirm the accuracy and robustness of ANNs for simulation of a single sprinkler distribution pattern under real field conditions.

Autonomous precision agriculture through integration of wireless underground sensor networks with center pivot irrigation systems

Precision agriculture (PA) refers to a series of practices and tools necessary to correctly evaluate farming needs. The accuracy and effectiveness of PA solutions are highly dependent on accurate and timely analysis of the soil conditions. In this paper, a proof-of-concept towards an autonomous precision irrigation system is provided through the integration of a center pivot (CP) irrigation system with wireless underground sensor networks (WUSNs). This Wireless Underground Sensor-Aided Center Pivot (WUSA-CP) system will provide autonomous irrigation management capabilities by monitoring the soil conditions in real time using wireless underground sensors. To this end, field experiments with a hydraulic drive and continuous-move center pivot irrigation system are conducted. The results are used to evaluate empirical channel models for soil-air communications. The experiment results show that the concept of WUSA-CP is feasible. Through the design of an underground antenna, communication ranges can be improved by up to 400% compared to conventional antenna designs. The results also highlight that the wireless communication channel between soil and air is significantly affected by many spatio-temporal aspects, such as the location and burial depth of the sensors, soil texture and physical properties, soil moisture, and the vegetation canopy height. To the best of our knowledge, this is the first work on the development of an autonomous precision irrigation system with WUSNs.

Economic viability of retrofiting emitters in center pivot irrigation systems

Although several studies have been conducted to evaluate the uniformity of water application under center pivot irrigation systems, there are few studies concerning the economic perspective of such coefficient. The aim of this study is to present a methodology to accomplish an economic analysis as support for the decision-making to retrofit emitters in center pivot irrigation systems, and to attribute an economic meaning to the uniformity coefficient of water application taking into account the response function productivity to the amount of water applied and the sale price of the crops. In the hypothetic calculation example considering the variation of revenue of potato crop under center pivot irrigation system, it was verified that the area with uniformity coefficient of water application of 90% brought an income increase of BR$ 1,992.00, considering an area about 1,0 ha. Thus, it can be concluded that the methodology presented has met the objectives proposed in the study and made it possible to attribute an economical meaning to the coefficient of water uniformity application.

Analysis of water application costs with a centre pivot system for irrigation of crops in Spain

The aim of this study was to present a methodology to analyse the main factors that influence annual water application costs in centre pivot irrigation systems and to determine the most cost-effective centre pivot design, given the variables of machine length, lateral pipe diameter, sprinkler type (LEPA and fixed and rotating spray plate sprinklers (FSPS and RSPS)), system capacity, application efficiency, and water and energy costs for the irrigation of crops such as maize under conditions in Spain. Annual water application costs were calculated as the sum of the investment (Ca), energy (Ce), water (Cw), and equipment maintenance costs (Cm). Parameters used to assess the influences on pivot design were system capacity Sc = 1.25 L s−1 ha−1; application efficiency Ea = 80% for FSPS, Ea = 85% for RSPS, and Ea = 90% for LEPA; water price Pw = 0.06 € m−3 (0.081 US dollars); energy price Ene = 0.10 € kWh−1 (0.135 US dollars); net annual crop irrigation water requirement Nn = 7,000 m3 ha−1 year−1; and net daily peak crop water requirement Nnmax = 7.63 mm d−1 for maize. Results indicate that for plots smaller than 30 ha, the recommended pipeline diameter is 127.0 mm (5 in); for 30–40 ha, 168.3 mm (6 5/8 in); for 40–75 ha, 219.1 mm (8 5/8 in); and for 75–100 ha, 254.0 mm (10 in). A multidiameter pipe solution only slightly reduced water application costs in most cases studied. It was also determined that water costs and irrigation efficiency have a major influence on the total annual cost of water application; however, system capacity and energy price did not strongly affect total cost. For this reason, water application uniformity is very important and can be accomplished using a proper nozzle package and regular maintenance. The paper helps farmers determine the most cost-effective centre pivot design and management.

Seasonal ammonia losses from spray-irrigation with secondary-treated recycled water

This work examines ammonia volatilization associated with agricultural irrigation employing recycled water. Effluent from a secondary wastewater treatment plant was applied using a center pivot irrigation system on a 12 ha agricultural site in Palmdale, California. Irrigation water was captured in shallow pans and ammonia concentrations were quantified in four seasonal events. The average ammonia loss ranged from 15 to 35% (averaging 22%) over 2-h periods. Temporal mass losses were well-fit using a first-order model. The resulting rate constants correlated primarily with temperature and secondarily with wind speed. The observed application rates and timing were projected over an entire irrigation season using meteorological time series data from the site, which yielded volatilization estimates of 0.03 to 0.09 metric tons NH(3)-N/ha per year. These rates are consistent with average rates (0.04 to 0.08 MT NH(3)-N/ha per year) based on 10 to 20 mg NH(3)-N/L effluent concentrations and a 22% average removal. As less than 10% of the treated effluent in California is currently reused, there is potential for this source to increase, but the increase may be offset by a corresponding reduction in synthetic fertilizers usage. This point is a factor for consideration with respect to nutrient management using recycled water.

Advances in Irrigation: Select Works From the 2010 Decennial Irrigation Symposium

This paper is an introduction to the Advances in Irrigation Special Collection in this issue of Transactions ASABE and the next issue of Applied Engineering in Agriculture of 14 papers selected from 88 papers and presentations at the ASABE 5th Decennial National Irrigation Symposium, December 2010, in Phoenix, Arizona. This symposium followed the objectives of the previous four decennial events to provide a forum to assess progress of research endeavors to advance the effectiveness of irrigation practices during the past 10 years, leading to further research priorities that respond to future challenges. The papers in this Collection address a wide range of topics grouped into broad categories: microirrigation, center pivot irrigation, crop water use for improved irrigation management, and smart irrigation controllers for landscape irrigation. While these papers are not inclusive of all irrigation work since the last decennial symposium, they do provide a snapshot of work considered important by researchers, funding agencies and other stakeholders. Many aspects of irrigation have changed since the first symposium in 1970. Although microirrigation is a small proportion of irrigated acreage, it will continue to increase in highly technical commercial food and fiber production as well as in subsistence farming. Center pivot irrigation systems have been an important tool to deliver water more efficiently in diverse settings. Advanced telemetry and control systems, developed during the past 10 years, are now common options for center pivots, but challenges remain to integrate those hardware developments into crop management practices. Possibilities are emerging for adding monitoring devices to center pivots to match crop water needs with water delivery. Energy balance models continue to be refined as tools to estimate crop water use from both ground and satellite based data. Evapotranspiration estimates are evolving from single location weather stations to whole-field or regional scopes. Finally, “smart” irrigation controllers have coupled evapotranspiration estimation or soil-water sensing with automated irrigation system water delivery. These controllers can increase the precision of irrigation to match crop or landscape water needs. Irrigation will continue to be an important practice for producing the world’s food. The irrigation research and education professions will need to respond to food production challenges with even more refined irrigation systems and water management in the next 10 years. However, research investment in irrigation continues to decline when important issues exist, such as: maintaining agricultural profitability with declining water supplies, integrating sensor-based information for real-time autonomous or semi-autonomous management, competition for limited water supplies between agriculture and other sectors, increasing energy cost, environmental impacts of irrigation, and use of alternative water sources (i.e., lower quality) for irrigation.

Uniformity of distribution of water and water depth applied in central pivot system in function of the relative position of the lateral line

An irrigation system should enable the efficient management of applied water. For this it is necessary to evaluate the performance of the system in operation. This study aimed to evaluate the uniformity of distribution, consumption of electricity and water depth applied by a center pivot irrigation system in function of the relative position of the lateral line. It was tested three positions of lines collecting water: incline of 3.45%, level and slope of 11.78%. The experimental design was completely randomized design with three repetitions at each position tested. It was applied the analysis of variance followed by Tukey test. The average coefficient of uniformity of Heermann & Hein was 90.02%, describing the uniformity of water distribution as very good. The mean weighted depth of irrigation applied was 5.84 mm, varying in each test significantly (5%) between the positions of slope versus incline and level. It was concluded that the position of the lateral line significantly influenced the uniformity of distribution, water applied and energy consumption.

Effects of irrigation withdrawals on streamflows in a karst environment: lower Flint River Basin, Georgia, USA

AbstractExtensive implementation of centre pivot irrigation systems occurred between 1970 and 1980 in the lower Flint River Basin (FRB) of southwestern Georgia, USA. Groundwater within this karstic system is in direct hydraulic connection with regional streams, many of which are incised through the overburden into underlying limestone. We used long‐term U.S. Geological Survey gaging station data to evaluate multiple flow metrics of two tributaries (Ichawaynochaway Creek and Spring Creek) in the lower FRB to determine the extent of changes in stream behaviour since irrigation practices intensified. We compared pre‐ and post‐irrigation flow duration curves, 1‐, 7‐, and 14‐day minimum flows, and 8‐day (seasonal) and annual baseflow recession slopes, in addition to evaluating regional climate data to determine whether significant differences existed between the pre‐ and post‐irrigation periods. Our results showed significant changes in low‐flow durations in the post‐irrigation record for both gages, including a decrease by an order of magnitude for 98% exceedance flows at Spring Creek. Both gages indicated significant reductions in 1‐, 7‐, and 14‐day low flows. Eight‐day baseflow recession curves (within early summer months) and annual baseflow recession curves became significantly steeper during the post‐irrigation period for Ichawaynochaway Creek. We also found that a significant relationship existed between winter and summer minimum flows in both streams in the pre‐irrigation period which was disrupted in post‐irrigation years. Regional climate data for the study period revealed no significant changes in rainfall totals or frequency of drought; however, there was evidence for a shift in seasonal rainfall patterns. Copyright © 2011 John Wiley & Sons, Ltd.

Developing Wind and/or Solar Powered Crop Irrigation Systems for the Great Plains

Some small scale, off-grid irrigation systems (< 2.5 ha) that are powered by wind or solar energy are cost effective, but this article discusses ways to achieve an economical renewable energy powered center pivot irrigation system for crops in the Great Plains. It was found that partitioning the center pivot irrigation system between a winter crop and a summer crop improved the match of wind turbine power generation to irrigation energy required. It was also found that a solar-photovoltaic (PV) array was a better match to the irrigation energy requirement of a winter and summer crop than using only a wind turbine, but a wind/solar hybrid was a better match than wind alone. Although solar PV systems were shown to be a better match than wind turbines for irrigation power requirements, solar PV systems are more expensive than small wind turbine systems for large-scale irrigation water requirements in the Great Plains. Including on-farm uses for the excess wind and solar electricity instead of selling the electricity back to a utility company at usually low prices, improves the profitability of a renewable energy powered irrigation system significantly. For a utility electrical price of $0.10/kWh, a wind turbine installed price of $3000/kW, no loan required (e.g. no loan costs), and the excess renewable energy generated electricity used for on-farm use only, a payback period of seven to eight years was possible with no state or federal incentives. With 55% federal incentives and the same assumptions, a payback period of four to five years was possible. Also, if the assumed operations and maintenance costs doubled, the payback period increased about two years. However, cost reductions are still required for both wind and solar energy systems in order that renewable energy systems can be competitive without the need for state or federal incentives when loans at 90% of installed cost with a 6% interest rate are required.